Repair of 70 year old cedar gutters

Our gutters have been leaking for years. When we first moved into this house I tried to stop the leaks by applying roofing tar, as had been done to them before, but that didn't help. We were nearly at the point of tearing them down and replacing them with metal gutters, but other than the leaks at the corner joints, they actually looked like they were in good shape.

Monya did some research on the web and found a place in California that specializes in wooden gutters, and they had a web site with instructions on how to do it yourself. If they had been located in Washington State, I would have tried to hire them, but since they weren't I decided to give it a try for myself.

So here's what a typical corner joint looked like after I had chipped, peeled, and pryed the tar and old caulk out of it. Notice that there is a "V" shape cut into the joint. That's where the caulk goes, allowing a generous amount of it to expand and contract with changes in temperature.

The next photo shows how it looked after I filled the joint with 50 year, non-hardening gutter seal caulk. One rainy day after finishing the joints like this proved that the gutters were not leaking at all any more.

Unfortunately, there was one spot where the joint between the gutter and the downspout had failed and caused the gutter to rot. I took out about 17 inches of old gutter and replaced it with a section of fir that nearly matches the shape of the original gutter. I had to round off the ends of the fir patch and chisel out a channel in the bottom to allow the water to flow smoothly.

Then I had to drill a new hole for the downspout. I sealed everything up water tight with gutter caulk and then painted the new wood with primer. A finish coat of paint will go on soon.